Abstract:
Environmental enrichment can improve animal welfare. As a method of environmental enrichment, the effect of different auditory stimulations on the behavior response and welfare of laying hen chicks has yet to be investigated. Therefore, this study was aimed at exploring the impact of various auditory exposures on the behavior, learning ability, and fear response of 4-week-old laying hen chicks. A total of 600 1-day-old chicks were randomly assigned to five different groups: C (control group), LM (Mozart\'s String Quartets, 65 to 75 dB), LN (recorded ventilation fans and machinery, 65 to 75 dB), HN (recorded ventilation fans and machinery, 85 to 95 dB), and HM (Mozart\'s String Quartets, 85 to 95 dB). The experiment was conducted from day 1 until the end of the experiment on day 28. Groups LM and LN were exposed to music and noise stimulation ranging from 65 to 75 dB. Groups HN and HM, meanwhile, received noise and music stimulation ranging from 85 to 95 dB. The control group (C) did not receive any additional auditory stimuli. During the experimental period, continuous behavioral recordings were made of each group of chicks from day 22 to day 28. On day 21, the PAL (one-trial passive avoidance learning) task was conducted. On days 23 and 24, OF (open field) and TI (tonic immobility) tests were performed, and the levels of serum CORT (corticosterone) and DA (dopamine) were measured. The results indicated that exposure to music and noise at intensities ranging from 85 to 95 dB could reduce comforting, preening, PAL avoidance rate, the total number of steps and grid crossings of OF, and the concentration of DA in 4 WOA chicks (p < 0.05), increase the freezing times of OF (p < 0.05); 65 to 75 dB of noise stimulation could reduce preening and total number steps of OF in 4 WOA chicks (p < 0.05), increase the freezing times of OF (p < 0.05); and 65 to 75 dB of music exposure could reduce the concentration of CORT in 4 WOA chicks (p < 0.05). Therefore, 65 to 75 dB of music exposure could produce positive effects on chicks and showed relatively low CORT level, whereas 85 to 95 dB of music and noise exposure could reduce comforting and preening behavior, impair learning ability, and increase the fear responses of chicks.
摘要:
丰富环境可以改善动物福利。作为一种环境富集的方法,不同听觉刺激对蛋鸡行为反应和福利的影响还有待研究。因此,这项研究旨在探索各种听觉暴露对行为的影响,学习能力,和4周龄蛋鸡的恐惧反应。总共600只1日龄雏鸡被随机分为五个不同的组:C(对照组),LM(莫扎特弦乐四重奏,65至75dB),LN(记录的通风风扇和机械,65至75dB),HN(记录的通风风扇和机械,85至95dB),和HM(莫扎特的弦乐四重奏,85至95dB)。从第1天进行实验,直到第28天实验结束。LM和LN组受到65至75dB的音乐和噪声刺激。组HN和HM,同时,收到的噪音和音乐刺激范围从85到95分贝。对照组(C)不接受任何额外的听觉刺激。在实验期间,从第22天到第28天,对每组雏鸡进行连续行为记录。在第21天,进行PAL(一次试验被动回避学习)任务。在第23天和第24天,进行了OF(开放场)和TI(强直性不动性)测试,测定血清CORT(皮质酮)和DA(多巴胺)水平。结果表明,在85至95dB的强度范围内暴露于音乐和噪声会降低舒适度,Preening,PAL回避率,OF的步数和网格交叉总数,和4只WOA雏鸡的DA浓度(p<0.05),增加OF的冻结时间(p<0.05);65至75dB的噪声刺激可以减少4只WOA雏鸡的肥厚和OF的总步数(p<0.05),增加OF的冷冻时间(p<0.05);音乐暴露65至75dB可以降低4只WOA雏鸡的CORT浓度(p<0.05)。因此,65至75分贝的音乐暴露可以对雏鸡产生积极影响,并显示相对较低的CORT水平,而85到95分贝的音乐和噪音暴露会降低安慰和美化行为,削弱学习能力,增加小鸡的恐惧反应。